This undated handout photo provided by the journal Science shows fossil hunting at Como Bluff. Scientists have figured out a way to take the temperature of dinosaurs, and it turns out to be almost the same as ours. Of course you can't just stick a thermometer under the tongue of a room-sized creature that's been extinct for millions of years. So they did the next best thing, they studied dinosaur teeth. (AP Photo/Wyoming Dinosaur International Society) less

This undated handout photo provided by the journal Science shows fossil hunting at Como Bluff. Scientists have figured out a way to take the temperature of dinosaurs, and it turns out to be almost the same as ... more

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This undated artist rendering provided by the journal Science shows a Jurassic sauropod. Scientists have figured out a way to take the temperature of dinosaurs, and it turns out to be almost the same as ours. Of course you can't just stick a thermometer under the tongue of a room-sized creature that's been extinct for millions of years. So they did the next best thing, they studied dinosaur teeth. (AP Photo/Illustrated by Russell Hawley, Tate Geological Museum) less

This undated artist rendering provided by the journal Science shows a Jurassic sauropod. Scientists have figured out a way to take the temperature of dinosaurs, and it turns out to be almost the same as ours. ... more

Photo: Russell Hawley

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This undated handout photo provided by the journal Science shows a Camarasaurus tooth from the Jurassic Morrison Formation of North America. Scientists have figured out a way to take the temperature of dinosaurs, and it turns out to be almost the same as ours. Of course you can't just stick a thermometer under the tongue of a room-sized creature that's been extinct for millions of years. So they did the next best thing, they studied dinosaur teeth. (AP Photo/Thomas Tutken, University of Bonn) less

This undated handout photo provided by the journal Science shows a Camarasaurus tooth from the Jurassic Morrison Formation of North America. Scientists have figured out a way to take the temperature of ... more

Photo: Thomas Tutken

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Dinosaur teeth offer clue to life as warm creatures

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WASHINGTON -- Scientists have figured out a way to take the temperature of dinosaurs, and it turns out to be almost the same as ours.

Of course you can't just stick a thermometer under the tongue of a gigantic creature that's been extinct for millions of years.

So they did the next best thing. They studied dinosaur teeth, which can reflect body temperature.

They found the long-necked Brachiosaurus had a temperature of about 100.8 degrees F and the smaller Camarasaurus had a temperature of about 98.3 degrees. People average 98.6.

Their study, reported online Thursday in the journal Science, won't settle the long-running debate over whether dinosaurs were warm-blooded like modern mammals or cold-blooded, requiring outside sources of warmth to get them going like lizards.

When they were first discovered, the theory was that they were lumbering and cold-blooded, but in recent years the consensus has been moving more toward warm-blooded, which would allow them to be more active, like the velociraptors in the Jurassic Park movies.

Their research was on sauropods, the largest of dinosaurs, and the researchers explained animals that large can retain body heat even with a relatively low metabolism, simply because they are so big. Brachiosaurus weighed in at 40 tons and Camarasaurus was a 15-ton creature. Both lived about 150 million years ago.

The finding "confirms that dinosaurs were not sluggish, cold-blooded animals," commented Roger Seymour of the University of Adelaide, Australia, who was not part of the research team.

But, he added, "the debate about dinosaur metabolic rate will go on, no doubt, because it can never be measured directly and paleoscientists will often seek evidence to support a particular view and ignore contrary evidence."

The new paper helps confirm what the temperatures of these dinosaurs were, but knowing what the temperature was in something so big doesn't necessarily confirm that it was warm-blooded, said Birchard, who was not part of the research team.

The researchers were able to determine the creatures' temperatures because body temperature makes a difference in the amount of different types of carbon and oxygen that collect in the tooth enamel.

Now that they've looked at the biggest ones, they plan to turn their attention to smaller dinosaurs.